Excavation bucket assemblies are used in the construction and mining. The bucket assemblies are used with a variety of different excavating apparatuses such as backhoes, power shovels, front-end loaders, dragline equipment, etc. Excavation bucket assemblies typically have a bucket body with a rear wall, sidewalls, and a bottom wall. The walls cooperatively define a region where excavated material can be contained and moved. The bottom, front edge of the bucket body can be coupled to a lip. Tooth assemblies are coupled to the lip to form an excavation bucket assembly.
Each tooth assembly can include an adapter and a tooth. The adapter can be coupled to the lip and a tooth can be coupled to the adapter. Pins can be used to couple the parts of the tooth assembly together and can be used to couple the tooth assembly to the lip. When a tooth becomes worn or damaged, the pin coupling the tooth to its corresponding adapter can be removed so that the tooth can be uncoupled from the adapter. A new tooth is then mounted in the place of the worn or damaged tooth.
During the tooth replacement process, the pin is knocked out with a large hammer. If the pin is damaged during this process, it is replaced with a new pin. Frequently replacing broken pins is undesirable as doing so increases the cost of maintaining the excavation bucket assembly. Moreover, using a large hammer to remove a pin can be dangerous. When striking the pin with a hammer, flying debris such as metal chips and sand can be created. The flying debris can potentially harm persons in the vicinity of the hammering.
An improvement over the conventional pin-based coupling systems is described in U.S. Pat. No. 6,216,368 by the same inventor as the present invention. It discloses a wedge-locking system that couples an adapter and a tooth together without the use of pins. Other details about the wedge-locking system are described in the U.S. patent, which is herein incorporated by reference in its entirety for all purposes. The wedge-locking system is present in a depression in the adapter. In this example, the depression is in the form of a rectangle and is defined by four slightly raised walls.
Over a period of time, particles such as grit or sand can get into the depression and can abrade the parts of the wedge-locking system and the adapter. Accordingly, when the operator uncouples the adapter and the tooth, the operator also cleans the depression of sand and grit. If the operator does not clean the depression well, particles can remain in the depression. When the wedge-locking system is in use, the particles lodged in the depression can continue to abrade the parts of the wedge-locking system and the adapter. The abrasion reduces the useful life of the wedge-locking system and the adapter. More frequent replacement of the wedge-locking system parts and the adapter may be required.
Embodiments of the invention address these and other problems.